First off, it's of prime importance to realize the battlefield role of each unit. If you think that massive waves of skinks with blowguns are going to evaporate enemy units with massed blowgun fire, you're sadly mistaken. That's not what skinks are for.

Skirmishing units of skinks are good at throwing away their lives to delay much stronger units. They might be able to cause a few wounds with blowdarts, but after moving, long range and multiple shots, they have BS ZERO. That means a unit of ten will maybe, just maybe cause a single wound on a single T3 target with no armor. So, what can they possibly be useful for?

Don't charge them in to help, their pitiful T2 will just give away combat resolution.

I've found them useful just as a speed bump to draw off a more powerful unit.

Maybe I shouldn't have started with the Skinks.

Saurus Warriors are the rock solid core of every Lizardmen army. I recommend blocks of twenty-five. They are solid across the board (except initiative). I don't give them spears. The extra armor save from hand weapon and shield is much more valuable. They need that armor to take a hit then hit back. Two attacks is their strength, they pack a punch.

Drop in a hero and you have a unit of stone cold killers. With cold-blooded and LD8, they have effective LD 9.2